The present invention relates generally to multi-section foldable agricultural implements and more specifically relates to a forwardly foldable implement designed to carry planter units.
As productivity becomes of increasing importance to the farmer, implement manufacturers must provide larger and wider implements designed to increase efficiency and output. As implements thus increase in size, transport and storage become more difficult.
Today several approaches are utilized to maximize implement width and yet minimize the storage and transport problems encountered. Many planter units are transported endwise while others utilize tandem hitch arrangements which permit adjacent sections to be joined prior to transport. Other units provide a cart or trailer on which the planter implement is transported and some manufacturers fold the planter frame either upwardly, rearwardly or forwardly. Each of these approaches, however, have encountered various problems when utilized with planter units.
Implements transported endwise are generally not folded prior to transport and accordingly have a transport length equal to their working width. As working width and therefore transport length is increased, transport maneuverability becomes more difficult since the unit will skid and tend to oversteer while being turned. Further, preparation of the unit for transport results in a considerable loss of operating time because the operating towbar on the implement front must be unhitched and the transport towbar on the implement end connected to the tractor.
Planters utilizing a tandem hitch arrangement can be effectively halved in length for transportation as the two sides are hitched together and then pulled either endwise or forwardly. To prepare this type of implement for transportation requires that the operator unhitch the unit, rearrange the sections and then rehitch the unit to his tractor. Accordingly, a considerable loss in operating time is encountered when this type of unit is converted between transport and field configurations.
Those planter units which utilize a cart or trailer for transporting the unit have the obvious disadvantage of additional expense incurred to provide a cart or trailer. Further, the operator incurs substantial lost time in moving the cart or trailer to the location of the planter when he is ready to move the planter to another field or to the storage site.
Many tillage implements such as cultivators and rod weeders are folded during transport and stoage. Recently available are implements having upwardly folding wing sections which transport and store the implement with its wing sections in a vertical position. The maximum width of the outer sections utilized in this type of implement is limited, however, since electrical wires and other types of overhanging obstacles present interference for folded outer sections. Unlike cultivators, planter units cannot easily be transported when elevated and rotated onto their sides since the seed and fertilizer contained in the hoppers spill. Further, the elevated units encounter significantly different stresses when suspended in this manner and thereby increase manufacturing and maintenance expenses. Such implements when folded also require some means of stabilizing the elevated wing sections thus further increasing the manufacturing costs and time lost by the operator in preparing the unit for transport or storage.
Another approach to providing more compact and transportable implements utilizes rearwardly folding wing sections. With this type of implement, the tools adjacent the section joints interfere with one another as the wing sections are folded rearwardly. Planter units extend rearwardly from the toolbar a distance greater than cultivator or other simple tillage units, and therefore the interference problem becomes even more significant. In addition, the trailing portion of rearwardly folding units have the tendency to skid during turns and maneuvers making them difficult to steer. To stabilize the trailing rear ends, a link or latch mechanism is generally provided. However, the operator has to dismount his tractor and secure the link or latch to lock the trailing sections together during the transport operation. While rearwardly folding implement frames provide a more simple solution to transport, the provision of planter units on rearwardly folding implements require that fertilizer drives and liquid tube distribution systems be disconnected when the wings are folded prior to actual transport.
It is also common to fold tillage and cultivator type units forwardly for transport. However, such implements cannot attain a very wide operating configuration unless the wing sections are of a significant length which then requires that a long hitch be provided between the tractor and the center frame. With the long hitch, however, the folded implement frame will not track well either during maneuvers in the field or during transport.